1. Technical Field
The present disclosure relates to a pointing and control device and a pointing and control method for a computer system.
2. Description of the Related Art
As is known, in order to improve the interaction of a user with a computer system, use of three-dimensional control and pointing devices has been invoked. Unlike typical two-dimensional control and pointing devices, such as a mouse, joy-stick or track-ball, just to mention some examples, three-dimensional devices detect their own displacements or rotations according to three distinct independent axes and hence enable a greater freedom of control. For example, three-dimensional devices can be used for simulating objects that are normally manipulated by the operator during use, such as pointers for presentations or sports implements in the case of videogames.
The movements are in general detected by gyroscopes and accelerometers. In particular, accelerometers are used to determine the direction of the acceleration of gravity, which defines an absolute reference, and linear accelerations, while gyroscopes are used to detect rotations and supply signals indicating the angular velocity of the pointing device about one or more axes. The acceleration and angular velocity signals must then be integrated one or more times to determine the position and direction of the pointing device to be used for control operations, such as control of the position of a cursor on the monitor of a computer system.
The operations of integration lead, however, to drawbacks, in particular because inevitable offsets and noise present in the acceleration and angular velocity signals add up and increase over time. The precision of control tends to decrease, and in order to eliminate temporarily the errors, periodic operations of recalibration or reset are necessary, which can temporarily interrupt use of the pointing device.
Following upon reset events and upon elimination of errors, sudden deviations may also occur, which in any case render control problematical and far from precise.